P679: SPOTLIGHT ON THE REAL-WORLD TREATMENT OF CML PTS IN GERMANY: A RETROSPECTIVE SURVEY IN PRIVATE ONCOLOGY PRACTICES
Authors: Georg-Nikolaus Franke, Gunnar Loewe, Marcel Reiser, Hartmut Linde, Andreas Josting, Eyck von der Heyde, Rudolf Weide, Hans Tesch, Arndt Nusch, Jolanta Dengler, Kathleen Jentsch-Ullrich
Journal: HemaSphere (2023)

Background: Primary care for patients (pts) with chronic myeloid leukemia (CML) in Germany is mainly provided by decentralized oncology practices. In contrast, clinical trials for new substances are usually carried out in specialized centers and university clinics, resulting in a lack of data on current treatment practice outside these centers. Aims: The aim of this study was to assess clinical routine treatment practice in pts with CML in real-world setting of private oncology practices in Germany. Methods: We retrospectively analyzed data of 819 CML pts from 43 practices. Pts with a confirmed diagnosis (dx) of CML in 2013 or later were eligible for inclusion. European Leukemia Net (ELN) recommendations for CML 2013 definitions were used for dx and response assessment. Data was entered anonymized by participating sites. Aggregated data per site was used for this analysis. Results: A total of 819 pts (mean age 58.5 years, range 15-91) were reviewed. CML specific risk scores at diagnosis were available for 343 (41.8%, EUTOS score in 86.0% of these pts) pts. 61.9% (n=503) pts had data available on spleen size and the calculated European long-term survival scores were high, intermediate, low in 53.0, 32.2 and 14.9% of pts, respectively. At dx, 84.2% (n=690) and 9.4% (n=77) pts were in chronic or accelerated phase, 0.7% (n=6) had a blast crisis and data was missing in 5.6% (n=46) pts. Molecular Monitoring was provided EUTOS certified laboratories for 87.7% (n=718). A typical BCR::ABL1 transcript was detected in 86.6% (n=709). Cytogenetics at dx were obtained in 71.2% (n=588) of pts. Mean time from initial dx to treatment was 1.2 months (m, range 0-92m). Molecular response was assessed after 2.8, 6.0, 9.4 and 12.9 m (mean) after start of treatment. 11.1% (69/623) of pts with available qPCR data did not achieve early molecular response (BCR::ABL1 IS ≤10% at 3 months). At 18 m, 83.7% (328/392) of pts with available PCR data had at least a major molecular response. Treatment had been changed to 2L in 41.5% (n=340) of pts (288: 2nd TKI, 2: HSCT, 50: off treatment) after a mean of 21.0 m. 56 pts had mutational analysis of the ABL1-kinase domain at the time of treatment change. The most common reason for 2L treatment were side effects (43.4%), followed by insufficient response (31.4%, suboptimal response or failure according to ELN 2013). Of the 288 pts switching to 2L treatment, 106 went on to 3L treatment (after a mean of 17.6 m, range 0-97 m) and 17 pts did not receive further treatment (figure 1). 2 pt entered a clinical trial. Molecular response assessments in 2L were done after 2.3, 5.3, 8.3, and 11.7 m (mean). 36.8 % (n=39/106) of all pts switched to and 92.8 % (n=39/42) of pts still on 3L treatment achieved BCR::ABL1% IS ≤1% at 12 m. 6 pts discontinued 3L and treatment was switched (HSCT:4, TKI: 23) after a mean time of 14.5 m (range 0.3-80.5 m). Reasons for change were side effects in 42.4%, insufficient response in 33.3%, and other reasons in 24.2% of pts. 8 pts were referred to a specialized center. Summary/Conclusion: Pts with CML in Germany are mainly treated in private practices. CML specific risk scores are used only in a minority of pts, whereas cytogenetic analysis at initial dx and molecular monitoring in a EUTOS certified lab were performed in most pts. Regardless of good molecular responses, 35.2% of pts received a 2L treatment, mainly due to adverse events. In contrast to ELN recommendations, cytogenetic or mutational analysis was performed only in a minority of pts with treatment failure. Referral to a specialized center or including pts into a clinical trial was rare. In conclusion, pts with CML in Germany are routinely monitored by PCR and good responses are achieved in the majority. Adherence to current treatment guidelines regarding diagnostics in pts with insufficient response should be ameliorated.Keywords: Real world data, Chronic myeloid leukemia